Powdered coal gasification system
By setting a differential pressure gauge and controlling the reaction temperature in the pulverized coal gasification system, the problem of slag outlet blockage was solved, enabling smooth slag discharge and efficient production in the gasifier, with the by-product steam used for power generation.
Patent Information
- Application Number
- CN202423132474.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-18
- Publication Date
- 2025-12-09
- Estimated Expiration
- 2034-12-18
AI Technical Summary
In a pulverized coal entrained gasifier, the slag inlet is prone to clogging, and coal ash easily adheres to the inner wall of the gasifier, affecting normal production.
Design a pulverized coal gasification system, including a reaction section, a heat exchange section, and a quench section of a gasifier. Install a differential pressure gauge at the slag outlet. By controlling the reaction temperature and the oxygen-to-pulverized coal ratio, ensure smooth slag discharge from the slag outlet and avoid coal ash adhesion.
It effectively prevents slag outlet blockage, ensures the normal operation of the gasifier, and uses the by-product high-temperature steam for power generation, thereby improving production efficiency.
Smart Images
Figure CN223646510U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of coal chemical technology, and in particular to a pulverized coal gasification system. Background Technology
[0002] The development of pulverized coal gasification technology will prompt upstream industries such as coal mining, washing, and transportation, as well as downstream industries such as coal chemical engineering and power generation, to upgrade their technologies to better adapt to the requirements of pulverized coal gasification and create a synergistic development environment. At the same time, upgrading pulverized coal gasification technology will also help reduce carbon dioxide emissions during coal utilization, promoting the coal industry towards a low-carbon and green development path.
[0003] In pulverized coal gasification technology, the commonly used coal gasification equipment is the pulverized coal fluidized bed gasifier. It has the following advantages: (1) Strong coal adaptability: It can use a variety of coals, including low-quality coal; (2) High gasification efficiency: The carbon conversion efficiency is usually over 99%, and the effective gas content is high; (3) Large single furnace capacity: It is suitable for large-scale coal chemical projects and combined cycle power generation, and can be produced on a large scale; (4) Good environmental protection: It generates less waste and is environmentally friendly.
[0004] Currently, pulverized coal fluidized bed gasifiers often experience slag outlet blockage due to unreasonable pulverized coal gasification system processes or improper production method control, causing coal ash to easily adhere to the inner wall of the gasifier. Utility Model Content
[0005] The purpose of this invention is to provide a pulverized coal gasification system to solve the problems of slag outlet blockage and coal ash easily sticking to the inner wall of the gasifier.
[0006] This utility model provides a pulverized coal gasification system, including a gasifier, which is divided into a reaction section, a heat exchange section, and a quench section. A pulverized coal burner is installed at the upper end of the reaction section, connected to a pulverized coal pipeline and an oxygen pipeline. The lower end of the reaction section is connected to the upper end of the heat exchange section. The transition point between the reaction section and the heat exchange section is a slag inlet. The lower end of the heat exchange section is connected to the upper end of the quench section. The side of the quench section is connected to a crude coal gas output pipeline. The lower end of the quench section is connected to a slag crusher. The lower end of the slag crusher is connected to the upper end of a slag lock hopper. The slag lock hopper is connected to a slag lock hopper flushing water tank. The upper part of the slag lock hopper is connected to a lock hopper circulation pump. The lock hopper circulation pump is connected to the lower part of the quench section. The lower end of the slag lock hopper is connected to a slag pool. The slag pool is connected to a slag pool pump. A slag remover is installed in the slag pool, and a vibrating dewatering screen for ash and slag dewatering is installed at the end of the slag remover.
[0007] Furthermore, the reaction section is a combustion chamber, the heat exchange section is a waste heat boiler, and the quenching section is a quenching chamber.
[0008] Furthermore, a differential pressure gauge is installed at the slag outlet to detect the pressure difference between the upper and lower ends of the slag outlet.
[0009] Furthermore, the slag pool pump is connected to the slag water output pipe and the fresh water inlet pipe.
[0010] Furthermore, the slag lock hopper flushing water tank is equipped with an inlet pipe and an outlet pipe, and a flushing water inlet pipe and a flushing water return pipe are provided between the slag lock hopper flushing water tank and the slag lock hopper.
[0011] Furthermore, the lock hopper circulation pump is connected to the lower part of the quench section via a slag lock hopper circulation pump return water pipeline.
[0012] Furthermore, a pulverized coal flow meter is installed on the pulverized coal pipeline, and an oxygen flow meter is installed on the oxygen pipeline.
[0013] Furthermore, a pressure gauge No. 1 is installed at the upper part of the reaction section, a pressure gauge No. 2 is installed at the upper part of the heat exchange section, a thermometer is installed in the middle of the heat exchange section, and a pressure gauge No. 3 is installed in the quenching section.
[0014] The method for producing pulverized coal using the above-mentioned pulverized coal gasification system includes the following steps:
[0015] (S1) High-pressure pulverized coal is introduced into the pulverized coal burner through the pulverized coal pipeline and injected at high speed into the reaction section of the gasifier. At the same time, oxygen is also introduced into the pulverized coal burner and injected at high speed into the reaction section of the gasifier.
[0016] (S2) Pulverized coal and oxygen react in the reaction section to generate high-temperature crude coal gas, which is mainly composed of carbon monoxide and hydrogen, and produce molten coal ash.
[0017] (S3) After the high-temperature crude gas and molten coal ash pass through the slag outlet, the temperature drops by 50-100℃, the viscosity of the coal ash decreases and the flow becomes worse. Then, after entering the heat exchange section, the crude gas is cooled down and the molten coal ash becomes solid ash slag.
[0018] (S4) Then the cooled crude gas and solid ash enter the quench section for further cooling and washing. The cooled crude gas is transported to the downstream process through the crude gas output pipeline. The solid ash remains at the bottom of the quench section after washing. The solid ash is crushed by the slag crusher and discharged into the slag lock hopper for depressurization. After depressurization, the ash is discharged into the slag pool. After being retrieved by the slag remover, the ash is dewatered by the vibrating dewatering screen to obtain coarse slag, which is then transported off-site.
[0019] Furthermore, in step (S2), the reaction pressure is ≤4.0 MPa and the reaction temperature is the critical viscosity temperature of pulverized coal.
[0020] The positive effects of this utility model are:
[0021] (1) In the method of pulverized coal gasification production described in this utility model, it is necessary to control the temperature of the reaction section of the gasifier to the critical viscosity temperature to ensure the effective reaction of pulverized coal and oxygen in the reaction section, and at the same time to smoothly discharge slag.
[0022] (2) In the method for producing pulverized coal gasification according to this utility model, the reaction temperature of pulverized coal and oxygen in the reaction section is the critical viscosity temperature of pulverized coal, that is, the reaction temperature is 1400~1410℃. When entering the heat exchange section, the temperature is the deformation temperature. The high-temperature crude coal gas and molten coal ash are 50~100℃ lower than the critical viscosity temperature of pulverized coal after passing through the slag outlet. In this way, the viscosity of the coal ash is reduced, the fluidity is worse, and it is not easy to stick to the heat exchange tubes of the waste heat exchanger in the heat exchange section.
[0023] (3) In the method of pulverized coal gasification production described in this utility model, the temperature of the heat exchange section is judged by observing the changes in the differential pressure gauge, whether there is a risk of slag outlet blockage, and whether molten coal ash will stick to the heat exchange tubes of the waste heat boiler in the heat exchange section. Because the reaction section is a liquid slag discharge section, the molten coal ash after the reaction must flow from the lower end of the reaction section to the waste heat boiler in the heat exchange section. To ensure that the differential pressure remains constant, smooth slag discharge and normal production operation can be guaranteed. Otherwise, blockage will cause production to stop. If the differential pressure gauge rises, it indicates that the reaction temperature is low and the slag outlet is blocked. The oxygen and pulverized coal ratio needs to be adjusted, i.e., the oxygen-coal ratio needs to be increased, thereby increasing the reaction temperature. If the differential pressure gauge drops, it indicates that the reaction temperature is too high. Molten slag will enter the waste heat boiler in the heat exchange section and easily stick to the heat exchange tubes of the waste heat boiler, affecting the heat exchange of the waste heat boiler. The oxygen-to-coal ratio needs to be adjusted, i.e., the oxygen-to-coal ratio needs to be reduced, to decrease the amount of molten ash adhering to the heat exchange tubes of the waste heat exchange section, ensuring effective heat exchange in the waste heat exchange section, and producing saturated steam at 320℃ and 9.8 MPa as a byproduct for turbine power generation. Attached Figure Description
[0024] The accompanying drawings are provided to better understand this solution and do not constitute a limitation of this disclosure. Wherein:
[0025] Figure 1 This is a schematic diagram of the pulverized coal gasification system described in this utility model.
[0026] The components include: 1. Reaction section; 2. Heat exchange section; 21. Slag inlet; 22. Differential pressure gauge; 3. Quenching section; 4. Pulverized coal burner; 41. Pulverized coal pipeline; 411. Pulverized coal flow meter; 42. Oxygen pipeline; 421. Oxygen flow meter; 5. Crude coal gas output pipeline; 6. Slag crusher; 7. Slag lock hopper; 8. Slag lock hopper flushing water tank; 81. Inlet water pipeline; 82. Outlet water pipeline; 83. Flushing water inlet water pipeline; 84. Flushing water return water pipeline; 9. Lock hopper circulation pump; 91. Slag lock hopper circulation pump return water pipeline; 10. Slag pool; 11. Slag pool pump; 110. Slag water output pipeline; 111. Fresh water inlet water pipeline; 12. Slag remover; 13. Vibrating dewatering screen; 101. Pressure gauge No. 1; 102. Pressure gauge No. 2; 103. Pressure gauge No. 3; 104. Thermometer. Detailed Implementation
[0027] The exemplary embodiments of this disclosure are described below with reference to the accompanying drawings, including various details of the embodiments to aid understanding, and should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this disclosure. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.
[0028] This utility model provides a pulverized coal gasification system, including a gasifier, which is divided into a reaction section 1, a heat exchange section 2, and a quench section 3. The reaction section 1 is a combustion chamber, the heat exchange section 2 is a waste heat boiler, and the quench section 3 is a quench chamber. A pulverized coal burner 4 is installed at the upper end of the reaction section 1, and the pulverized coal burner 4 is connected to a pulverized coal pipeline 41 and an oxygen pipeline 42. The lower end of the reaction section 1 is connected to the upper end of the heat exchange section 2, and the transition point between the reaction section 1 and the heat exchange section 2 is a slag inlet 21. The lower end of the heat exchange section 2 is connected to the upper end of the quench section 3. The side of section 3 is connected to the crude gas output pipe 5. The lower end of the quench section 3 is connected to the slag crusher 6. The lower end of the slag crusher 6 is connected to the upper end of the slag lock hopper 7. The slag lock hopper 7 is connected to the slag lock hopper flushing water tank 8. The upper part of the slag lock hopper 7 is connected to the lock hopper circulation pump 9. The lock hopper circulation pump 9 is connected to the lower part of the quench section 3. The lower end of the slag lock hopper 7 is connected to the slag pool 10. The slag pool 10 is connected to the slag pool pump 11. The slag pool 10 contains a slag remover 12. The end of the slag remover 12 is equipped with a vibrating dewatering screen 13 for ash and slag dewatering.
[0029] Furthermore, the slag pool pump 11 is connected to the slag water output pipe 110 and the fresh water inlet pipe 111. The black water in the slag pool 10 is transported to the slag water treatment process section through the slag water output pipe 110 via the slag water pump 11. Then, fresh water is injected into the slag pool 10 through the fresh water inlet pipe 111, achieving water circulation in the slag pool. A flushing water inlet pipe 83 and a flushing water return pipe 84 are provided between the slag lock hopper flushing water tank 8 and the slag lock hopper 7. Flushing water is injected into the slag lock hopper 7 through the flushing water inlet pipe 83, and the flushed water is transported to the slag lock hopper flushing water tank 8 through the flushing water return pipe 84. The slag lock hopper flushing water tank 8 is equipped with an inlet pipe 81 and an outlet pipe 82. Flushing wastewater is transported to the wastewater treatment process section through the outlet pipe 82, and then fresh water is injected into the slag lock hopper flushing water tank 8 through the inlet pipe 81, achieving water circulation in the slag pool. The lock bucket circulation pump 9 is connected to the lower part of the quench section 3 through the slag lock bucket circulation pump return water pipe 91. Water is transported to the lower part of the quench section 3 through the slag lock bucket circulation pump return water pipe 91 to wash the solid ash slag.
[0030] Furthermore, a differential pressure gauge 22 is installed at the slag outlet 21 to detect the pressure difference between the upper and lower ends of the slag outlet 21. A pulverized coal flow meter 411 is installed on the pulverized coal pipeline 41, and an oxygen flow meter 421 is installed on the oxygen pipeline 42. A pressure gauge 101 is installed at the upper part of the reaction section 1, a pressure gauge 102 is installed at the upper part of the heat exchange section 2, a thermometer 104 is installed in the middle of the heat exchange section 2, and a pressure gauge 103 is installed in the quench section 3.
[0031] The method for producing pulverized coal using the above-mentioned pulverized coal gasification system includes the following steps:
[0032] (S1) High-pressure pulverized coal is introduced into the pulverized coal burner 4 through the pulverized coal pipe 41 and injected at high speed into the reaction section 1 of the gasifier. At the same time, oxygen is also introduced into the pulverized coal burner 4 and injected at high speed into the reaction section 1 of the gasifier.
[0033] (S2) Pulverized coal and oxygen react in reaction section 1 at a reaction pressure of ≤4.0 MPa and a reaction temperature of the critical viscosity temperature of pulverized coal, which is 1400~1410℃, to generate high-temperature crude coal gas mainly composed of carbon monoxide and hydrogen, and to produce molten coal ash.
[0034] (S3) After the high-temperature crude gas and molten coal ash pass through the slag inlet 21, the temperature drops by 50-100°C, the viscosity of the coal ash decreases and the flow becomes worse, and then it enters the heat exchange section 2. It uses its own high-grade heat energy to exchange heat with the waste boiler feedwater in the heat exchange section 2, so that the crude gas cools down and the molten coal ash becomes solid ash slag; at the same time, the high-pressure waste boiler feedwater is heated to generate saturated steam at 320°C and 9.8 MPa, which is then used for steam turbine power generation.
[0035] (S4) Then the cooled crude gas and solid ash enter the quenching section 3 for further cooling and washing. The cooled crude gas is transported to the downstream process through the crude gas output pipeline 5. The solid ash remains at the bottom of the quenching section 3 after washing. The solid ash is crushed by the slag crusher 6 and discharged into the slag lock hopper 7 for depressurization. After depressurization, the ash is discharged into the slag pool 10. After being scooped out by the slag remover 12, the ash is dewatered by the vibrating dewatering screen 13 to obtain coarse slag. The coarse slag is transported to the brick factory as raw material for brick making.
[0036] In the method for producing pulverized coal gasification according to this invention, the critical viscosity temperature of pulverized coal is determined by viscosity testing, i.e., the critical viscosity temperature.
[0037] In the method for producing pulverized coal gasification according to this invention, the temperature of the reaction section 1 of the gasifier needs to be controlled at the critical viscosity temperature to ensure effective reaction between pulverized coal and oxygen in the reaction section 1, while also ensuring smooth slag discharge. The reaction temperature of pulverized coal and oxygen in the reaction section 1 is the critical viscosity temperature of the pulverized coal, i.e., 1400–1410℃. Upon entering the heat exchange section 2, the temperature is the deformation temperature. The high-temperature crude gas and molten coal ash, after passing through the slag outlet 21, have a temperature 50–100℃ lower than the critical viscosity temperature of the pulverized coal. This reduces the viscosity of the coal ash, decreases its fluidity, and makes it less likely to adhere to the heat exchange tubes of the waste heat exchanger in the waste heat exchange section 2.
[0038] In addition, observation is required. Figure 1 The changes in the differential pressure gauge 22 are used to determine whether the temperature of heat exchange section 2 is reasonable, whether there is a risk of blockage at slag outlet 21, and whether molten coal ash will adhere to the heat exchange tubes of the waste heat boiler in heat exchange section 2. Because reaction section 1 involves liquid slag discharge, the molten coal ash from the reaction section must flow from the lower end of reaction section 1 to the waste heat boiler in heat exchange section 2. Maintaining a constant differential pressure is crucial for smooth slag discharge and normal production operation; otherwise, blockage will cause production shutdown. If the differential pressure gauge 22 increases, it indicates that the reaction temperature is low and slag outlet 21 is blocked. The oxygen-to-coal ratio needs to be adjusted, i.e., the oxygen-to-coal ratio needs to be increased, thereby raising the reaction temperature. If the differential pressure gauge 22 decreases, it indicates that the reaction temperature is too high, and molten slag will enter the waste heat boiler in heat exchange section 2, easily adhering to the heat exchange tubes and affecting heat exchange in the waste heat boiler. The oxygen and pulverized coal ratio needs to be adjusted, i.e., the oxygen-coal ratio needs to be reduced, to reduce the adhesion of molten ash to the heat exchange tubes of the waste boiler in heat exchange section 2, and to ensure effective heat exchange in the waste boiler of heat exchange section 2, so as to produce saturated steam at 320℃ and 9.8 MPa by-products for steam turbine power generation.
[0039] Example 1: Pulverized Coal Gasification System
[0040] This utility model provides a pulverized coal gasification system, the schematic diagram of which is shown below. Figure 1The system includes a gasifier, which is divided into a reaction section 1, a heat exchange section 2, and a quench section 3. The reaction section 1 is a combustion chamber, the heat exchange section 2 is a waste heat boiler, and the quench section 3 is a quench chamber. A pulverized coal burner 4 is installed at the upper end of the reaction section 1, and the pulverized coal burner 4 is connected to a pulverized coal pipeline 41 and an oxygen pipeline 42. The lower end of the reaction section 1 is connected to the upper end of the heat exchange section 2. The transition point between the reaction section 1 and the heat exchange section 2 is a slag inlet 21. The lower end of the heat exchange section 2 is connected to the upper end of the quench section 3, and the side of the quench section 3 is flush with the coarse coal. The gas output pipe 5 is connected, the lower end of the quench section 3 is connected to the slag crusher 6, the lower end of the slag crusher 6 is connected to the upper end of the slag lock hopper 7, the slag lock hopper 7 is connected to the slag lock hopper flushing water tank 8, the upper part of the slag lock hopper 7 is connected to the lock hopper circulation pump 9, the lock hopper circulation pump 9 is connected to the lower part of the quench section 3, the lower end of the slag lock hopper 7 is connected to the slag pool 10, the slag pool 10 is connected to the slag pool pump 11, the slag pool 10 contains a slag remover 12, and the end of the slag remover 12 is equipped with a vibrating dewatering screen 13 for ash and slag dewatering.
[0041] The slag pool pump 11 is connected to the slag water output pipe 110 and the fresh water inlet pipe 111. The slag lock hopper flushing water tank 8 is equipped with an inlet pipe 81 and an outlet pipe 82. A flushing water inlet pipe 83 and a flushing water return pipe 84 are provided between the slag lock hopper 7 and the slag lock hopper. The lock hopper circulation pump 9 is connected to the lower part of the quench section 3 via the slag lock hopper circulation pump return pipe 91.
[0042] In addition, a differential pressure gauge 22 is installed at the slag outlet 21 to detect the pressure difference between the upper and lower ends of the slag outlet 21. A pulverized coal flow meter 411 is installed on the pulverized coal pipeline 41, and an oxygen flow meter 421 is installed on the oxygen pipeline 42. A pressure gauge 101 is installed at the upper part of the reaction section 1, a pressure gauge 102 is installed at the upper part of the heat exchange section 2, a thermometer 104 is installed in the middle of the heat exchange section 2, and a pressure gauge 103 is installed in the quench section 3.
[0043] Example 2: Pulverized Coal Gasification System
[0044] This utility model provides a pulverized coal gasification system, including a gasifier, which is divided into a reaction section 1, a heat exchange section 2, and a quench section 3. The reaction section 1 is a combustion chamber, the heat exchange section 2 is a waste heat boiler, and the quench section 3 is a quench chamber. A pulverized coal burner 4 is installed at the upper end of the reaction section 1, and the pulverized coal burner 4 is connected to a pulverized coal pipeline 41 and an oxygen pipeline 42. The lower end of the reaction section 1 is connected to the upper end of the heat exchange section 2, and the transition point between the reaction section 1 and the heat exchange section 2 is a slag inlet 21. The lower end of the heat exchange section 2 is connected to the upper end of the quench section 3. The side of section 3 is connected to the crude gas output pipe 5. The lower end of the quench section 3 is connected to the slag crusher 6. The lower end of the slag crusher 6 is connected to the upper end of the slag lock hopper 7. The slag lock hopper 7 is connected to the slag lock hopper flushing water tank 8. The upper part of the slag lock hopper 7 is connected to the lock hopper circulation pump 9. The lock hopper circulation pump 9 is connected to the lower part of the quench section 3. The lower end of the slag lock hopper 7 is connected to the slag pool 10. The slag pool 10 is connected to the slag pool pump 11. The slag pool 10 contains a slag remover 12. The end of the slag remover 12 is equipped with a vibrating dewatering screen 13 for ash and slag dewatering.
[0045] Example 3: Pulverized Coal Gasification System
[0046] This utility model provides a pulverized coal gasification system, including a gasifier, which is divided into a reaction section 1, a heat exchange section 2, and a quench section 3. The reaction section 1 is a combustion chamber, the heat exchange section 2 is a waste heat boiler, and the quench section 3 is a quench chamber. A pulverized coal burner 4 is installed at the upper end of the reaction section 1, and the pulverized coal burner 4 is connected to a pulverized coal pipeline 41 and an oxygen pipeline 42. The lower end of the reaction section 1 is connected to the upper end of the heat exchange section 2, and the transition point between the reaction section 1 and the heat exchange section 2 is a slag inlet 21. The lower end of the heat exchange section 2 is connected to the upper end of the quench section 3. The side of section 3 is connected to the crude gas output pipe 5. The lower end of the quench section 3 is connected to the slag crusher 6. The lower end of the slag crusher 6 is connected to the upper end of the slag lock hopper 7. The slag lock hopper 7 is connected to the slag lock hopper flushing water tank 8. The upper part of the slag lock hopper 7 is connected to the lock hopper circulation pump 9. The lock hopper circulation pump 9 is connected to the lower part of the quench section 3. The lower end of the slag lock hopper 7 is connected to the slag pool 10. The slag pool 10 is connected to the slag pool pump 11. The slag pool 10 contains a slag remover 12. The end of the slag remover 12 is equipped with a vibrating dewatering screen 13 for ash and slag dewatering.
[0047] The slag pool pump 11 is connected to the slag water output pipe 110 and the fresh water inlet pipe 111. The slag lock hopper flushing water tank 8 is equipped with an inlet pipe 81 and an outlet pipe 82. A flushing water inlet pipe 83 and a flushing water return pipe 84 are provided between the slag lock hopper 7 and the slag lock hopper. The lock hopper circulation pump 9 is connected to the lower part of the quench section 3 via the slag lock hopper circulation pump return pipe 91.
[0048] Example 4: Pulverized Coal Gasification System
[0049] This utility model provides a pulverized coal gasification system, including a gasifier, which is divided into a reaction section 1, a heat exchange section 2, and a quench section 3. The reaction section 1 is a combustion chamber, the heat exchange section 2 is a waste heat boiler, and the quench section 3 is a quench chamber. A pulverized coal burner 4 is installed at the upper end of the reaction section 1, and the pulverized coal burner 4 is connected to a pulverized coal pipeline 41 and an oxygen pipeline 42. The lower end of the reaction section 1 is connected to the upper end of the heat exchange section 2, and the transition point between the reaction section 1 and the heat exchange section 2 is a slag inlet 21. The lower end of the heat exchange section 2 is connected to the upper end of the quench section 3. The side of section 3 is connected to the crude gas output pipe 5. The lower end of the quench section 3 is connected to the slag crusher 6. The lower end of the slag crusher 6 is connected to the upper end of the slag lock hopper 7. The slag lock hopper 7 is connected to the slag lock hopper flushing water tank 8. The upper part of the slag lock hopper 7 is connected to the lock hopper circulation pump 9. The lock hopper circulation pump 9 is connected to the lower part of the quench section 3. The lower end of the slag lock hopper 7 is connected to the slag pool 10. The slag pool 10 is connected to the slag pool pump 11. The slag pool 10 contains a slag remover 12. The end of the slag remover 12 is equipped with a vibrating dewatering screen 13 for ash and slag dewatering.
[0050] A differential pressure gauge 22 is installed at the slag outlet 21 to detect the pressure difference between the upper and lower ends of the slag outlet 21. A pulverized coal flow meter 411 is installed on the pulverized coal pipeline 41, and an oxygen flow meter 421 is installed on the oxygen pipeline 42. A pressure gauge 101 is installed at the upper part of the reaction section 1, a pressure gauge 102 is installed at the upper part of the heat exchange section 2, a thermometer 104 is installed in the middle of the heat exchange section 2, and a pressure gauge 103 is installed in the quench section 3.
[0051] Example 5: Method for producing coal gasification
[0052] The method for producing pulverized coal using the pulverized coal gasification system described in Example 1 includes the following steps:
[0053] (S1) High-pressure pulverized coal is introduced into the pulverized coal burner 4 through the pulverized coal pipeline 41 and injected at high speed into the reaction section 1 of the gasifier. At the same time, oxygen is also introduced into the pulverized coal burner 4 and injected at high speed into the reaction section 1 of the gasifier.
[0054] (S2) Pulverized coal and oxygen react in reaction section 1 at a pressure of 4.0 MPa and a temperature equal to the critical viscosity temperature of pulverized coal, which is 1400℃. This produces high-temperature crude coal gas, which is mainly composed of carbon monoxide and hydrogen, and generates molten coal ash.
[0055] (S3) After the high-temperature crude gas and molten coal ash pass through slag inlet 21, the temperature drops by 50°C to 1350°C. The viscosity of the coal ash decreases, and its flow becomes less efficient. Then, entering heat exchange section 2, the gas utilizes its high-temperature heat energy to exchange heat with the wastewater from the boiler in section 2, causing the crude gas to cool and the molten coal ash to solidify into solid ash. During the heat exchange process, observation is necessary. Figure 1 The changes in the differential pressure gauge 22 are used to determine whether the temperature of heat exchange section 2 is reasonable, whether there is a risk of blockage at slag outlet 21, and whether molten coal ash will adhere to the heat exchange tubes of the waste heat boiler in heat exchange section 2. Because reaction section 1 involves liquid slag discharge, the molten coal ash from the reaction section must flow from the lower end of reaction section 1 to the waste heat boiler in heat exchange section 2. Maintaining a constant differential pressure is crucial for smooth slag discharge and normal production operation; otherwise, blockage will cause production shutdown. If the differential pressure gauge 22 increases, it indicates that the reaction temperature is low and slag outlet 21 is blocked. The oxygen-to-coal ratio needs to be adjusted, i.e., the oxygen-to-coal ratio needs to be increased, thereby raising the reaction temperature. If the differential pressure gauge 22 decreases, it indicates that the reaction temperature is too high, and molten slag will enter the waste heat boiler in heat exchange section 2, easily adhering to the heat exchange tubes and affecting heat exchange in the waste heat boiler. The oxygen and pulverized coal ratio needs to be adjusted, i.e., the oxygen-coal ratio needs to be reduced, to reduce the adhesion of molten ash to the heat exchange tubes of the waste boiler in heat exchange section 2, and to ensure effective heat exchange in the waste boiler of heat exchange section 2, so as to produce saturated steam at 320℃ and 9.8 MPa by-products for steam turbine power generation.
[0056] (S4) Then the cooled crude gas and solid ash enter the quenching section 3 for further cooling and washing. The cooled crude gas is transported to the downstream process through the crude gas output pipeline 5. The solid ash remains at the bottom of the quenching section 3 after washing. The solid ash is crushed by the slag crusher 6 and discharged into the slag lock hopper 7 for depressurization. After depressurization, the ash is discharged into the slag pool 10. After being scooped out by the slag remover 12, the ash is dewatered by the vibrating dewatering screen 13 to obtain coarse slag. The coarse slag is transported to the brick factory as raw material for brick making.
[0057] Example 6: Method for producing coal gasification
[0058] The method for producing pulverized coal using the pulverized coal gasification system described in Example 1 includes the following steps:
[0059] (S1) High-pressure pulverized coal is introduced into the pulverized coal burner 4 through the pulverized coal pipeline 41 and injected at high speed into the reaction section 1 of the gasifier. At the same time, oxygen is also introduced into the pulverized coal burner 4 and injected at high speed into the reaction section 1 of the gasifier.
[0060] (S2) Pulverized coal and oxygen react in reaction section 1 at a pressure of 3.0 MPa and a temperature equal to the critical viscosity temperature of pulverized coal, which is 1410℃. This produces high-temperature crude coal gas, which is mainly composed of carbon monoxide and hydrogen, and generates molten coal ash.
[0061] (S3) After the high-temperature crude gas and molten coal ash pass through slag inlet 21, the temperature drops by 70°C, the viscosity of the coal ash decreases, and its flow becomes poorer. Then, entering heat exchange section 2, the coal ash utilizes its high-temperature heat energy to exchange heat with the wastewater from the boiler in heat exchange section 2, causing the crude gas to cool down and the molten coal ash to solidify into solid ash slag. During the heat exchange process, observation is necessary. Figure 1 The changes in the differential pressure gauge 22 are used to determine whether the temperature of heat exchange section 2 is reasonable, whether there is a risk of blockage at slag outlet 21, and whether molten coal ash will adhere to the heat exchange tubes of the waste heat boiler in heat exchange section 2. Because reaction section 1 involves liquid slag discharge, the molten coal ash from the reaction section must flow from the lower end of reaction section 1 to the waste heat boiler in heat exchange section 2. Maintaining a constant differential pressure is crucial for smooth slag discharge and normal production operation; otherwise, blockage will cause production shutdown. If the differential pressure gauge 22 increases, it indicates that the reaction temperature is low and slag outlet 21 is blocked. The oxygen-to-coal ratio needs to be adjusted, i.e., the oxygen-to-coal ratio needs to be increased, thereby raising the reaction temperature. If the differential pressure gauge 22 decreases, it indicates that the reaction temperature is too high, and molten slag will enter the waste heat boiler in heat exchange section 2, easily adhering to the heat exchange tubes and affecting heat exchange in the waste heat boiler. The oxygen and pulverized coal ratio needs to be adjusted, i.e., the oxygen-coal ratio needs to be reduced, to reduce the adhesion of molten ash to the heat exchange tubes of the waste boiler in heat exchange section 2, and to ensure effective heat exchange in the waste boiler of heat exchange section 2, so as to produce saturated steam at 320℃ and 9.8 MPa by-products for steam turbine power generation.
[0062] (S4) Then the cooled crude gas and solid ash enter the quenching section 3 for further cooling and washing. The cooled crude gas is transported to the downstream process through the crude gas output pipeline 5. The solid ash remains at the bottom of the quenching section 3 after washing. The solid ash is crushed by the slag crusher 6 and discharged into the slag lock hopper 7 for depressurization. After depressurization, the ash is discharged into the slag pool 10. After being scooped out by the slag remover 12, the ash is dewatered by the vibrating dewatering screen 13 to obtain coarse slag. The coarse slag is transported to the brick factory as raw material for brick making.
[0063] Example 7: Method for producing coal gasification
[0064] The method for producing pulverized coal using the pulverized coal gasification system described in Example 1 includes the following steps:
[0065] (S1) High-pressure pulverized coal is introduced into the pulverized coal burner 4 through the pulverized coal pipeline 41 and injected at high speed into the reaction section 1 of the gasifier. At the same time, oxygen is also introduced into the pulverized coal burner 4 and injected at high speed into the reaction section 1 of the gasifier.
[0066] (S2) Pulverized coal and oxygen react in reaction section 1 at a pressure of 2.0 MPa and a temperature equal to the critical viscosity temperature of pulverized coal, which is 1405℃. High-temperature crude coal gas, mainly composed of carbon monoxide and hydrogen, is generated, and molten coal ash is produced.
[0067] (S3) After the high-temperature crude gas and molten coal ash pass through slag inlet 21, the temperature drops by 100°C, the viscosity of the coal ash decreases, and its flow becomes poorer. Then, entering heat exchange section 2, the coal ash utilizes its high-temperature heat energy to exchange heat with the wastewater from the boiler in heat exchange section 2, causing the crude gas to cool down and the molten coal ash to solidify into solid ash slag. During the heat exchange process, observation is necessary. Figure 1 The changes in the differential pressure gauge 22 are used to determine whether the temperature of heat exchange section 2 is reasonable, whether there is a risk of blockage at slag outlet 21, and whether molten coal ash will adhere to the heat exchange tubes of the waste heat boiler in heat exchange section 2. Because reaction section 1 involves liquid slag discharge, the molten coal ash from the reaction section must flow from the lower end of reaction section 1 to the waste heat boiler in heat exchange section 2. Maintaining a constant differential pressure is crucial for smooth slag discharge and normal production operation; otherwise, blockage will cause production shutdown. If the differential pressure gauge 22 increases, it indicates that the reaction temperature is low and slag outlet 21 is blocked. The oxygen-to-coal ratio needs to be adjusted, i.e., the oxygen-to-coal ratio needs to be increased, thereby raising the reaction temperature. If the differential pressure gauge 22 decreases, it indicates that the reaction temperature is too high, and molten slag will enter the waste heat boiler in heat exchange section 2, easily adhering to the heat exchange tubes and affecting heat exchange in the waste heat boiler. The oxygen and pulverized coal ratio needs to be adjusted, i.e., the oxygen-coal ratio needs to be reduced, to reduce the adhesion of molten ash to the heat exchange tubes of the waste boiler in heat exchange section 2, and to ensure effective heat exchange in the waste boiler of heat exchange section 2, so as to produce saturated steam at 320℃ and 9.8 MPa by-products for steam turbine power generation.
[0068] (S4) Then the cooled crude gas and solid ash enter the quenching section 3 for further cooling and washing. The cooled crude gas is transported to the downstream process through the crude gas output pipeline 5. The solid ash remains at the bottom of the quenching section 3 after washing. The solid ash is crushed by the slag crusher 6 and discharged into the slag lock hopper 7 for depressurization. After depressurization, the ash is discharged into the slag pool 10. After being scooped out by the slag remover 12, the ash is dewatered by the vibrating dewatering screen 13 to obtain coarse slag. The coarse slag is transported to the brick factory as raw material for brick making.
[0069] Example 8: Method for producing coal gasification
[0070] The method for producing pulverized coal using the pulverized coal gasification system described in Example 4 includes the following steps:
[0071] (S1) High-pressure pulverized coal is introduced into the pulverized coal burner 4 through the pulverized coal pipeline 41 and injected at high speed into the reaction section 1 of the gasifier. At the same time, oxygen is also introduced into the pulverized coal burner 4 and injected at high speed into the reaction section 1 of the gasifier.
[0072] (S2) Pulverized coal and oxygen react in reaction section 1 at a pressure of 4.0 MPa and a temperature equal to the critical viscosity temperature of pulverized coal, which is 1410℃. This produces high-temperature crude coal gas, which is mainly composed of carbon monoxide and hydrogen, and generates molten coal ash.
[0073] (S3) After the high-temperature crude gas and molten coal ash pass through slag outlet 21, the temperature drops by 100°C to 1350°C. The viscosity of the coal ash decreases, and its flow becomes less efficient. Then, it enters heat exchange section 2 and uses its high-temperature heat energy to exchange heat with the feedwater in the waste boiler of heat exchange section 2, causing the crude gas to cool down and the molten coal ash to become solid ash. During the heat exchange process, it is necessary to observe the changes in differential pressure gauge 22 to determine whether the temperature of heat exchange section 2 is reasonable, whether there is a risk of blockage at slag outlet 21, and whether molten coal ash will adhere to the heat exchange tubes of the waste boiler in heat exchange section 2. Because reaction section 1 is a liquid slag discharge, the molten coal ash after reaction must flow from the lower end of reaction section 1 to the waste boiler in heat exchange section 2. Maintaining a constant differential pressure is crucial for smooth slag discharge and normal production operation; otherwise, blockage will cause production shutdown. If the differential pressure gauge 22 increases, it indicates that the reaction temperature is low and slag outlet 21 is blocked. The oxygen and pulverized coal ratio needs to be adjusted, i.e., the oxygen-coal ratio needs to be increased, thereby increasing the reaction temperature. If the differential pressure gauge 22 decreases, it indicates that the reaction temperature is too high, and molten slag will enter the waste boiler of heat exchange section 2. This slag is likely to adhere to the heat exchange tubes of the waste boiler, affecting heat exchange. The oxygen-to-coal ratio needs to be adjusted, i.e., the oxygen-to-coal ratio needs to be reduced, to decrease the adhesion of molten slag to the heat exchange tubes of the waste boiler in heat exchange section 2, ensuring effective heat exchange in the waste boiler.
[0074] (S4) Then the cooled crude gas and solid ash enter the quenching section 3 for further cooling and washing. The cooled crude gas is transported to the downstream process through the crude gas output pipeline 5. The solid ash remains at the bottom of the quenching section 3 after washing. The solid ash is crushed by the slag crusher 6 and discharged into the slag lock hopper 7 for depressurization. After depressurization, the ash is discharged into the slag pool 10. After being scooped out by the slag remover 12, the ash is dewatered by the vibrating dewatering screen 13 to obtain coarse slag. The coarse slag is transported to the brick factory as raw material for brick making.
[0075] It should be understood that the steps of the pulverized coal gasification system and the pulverized coal gasification production method described above can be rearranged, added, or deleted. This utility model does not impose any limitations on the results achieved as long as the desired outcome of the disclosed technical solution can be achieved.
[0076] The specific embodiments described above do not constitute a limitation on the scope of protection disclosed in this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection disclosed in this utility model.
Claims
1. A pulverized coal gasification system, characterized in that: The system includes a gasifier, which is divided into a reaction section (1), a heat exchange section (2), and a quench section (3). A pulverized coal burner (4) is installed at the upper end of the reaction section (1), and the pulverized coal burner (4) is connected to a pulverized coal pipeline (41) and an oxygen pipeline (42). The lower end of the reaction section (1) is connected to the upper end of the heat exchange section (2). The transition point between the reaction section (1) and the heat exchange section (2) is a slag outlet (21). The lower end of the heat exchange section (2) is connected to the upper end of the quench section (3). The side of the quench section (3) is connected to a crude gas output pipeline (5). The lower end is connected to the slag crusher (6), the lower end of the slag crusher (6) is connected to the upper end of the slag lock hopper (7), the slag lock hopper (7) is connected to the slag lock hopper flushing water tank (8), the upper part of the slag lock hopper (7) is connected to the lock hopper circulation pump (9), the lock hopper circulation pump (9) is connected to the lower part of the quenching section (3), the lower end of the slag lock hopper (7) is connected to the slag pool (10), the slag pool (10) is connected to the slag pool pump (11), the slag pool (10) contains a slag remover (12), and the end of the slag remover (12) is equipped with a vibrating dewatering screen (13) for ash and slag dewatering.
2. The pulverized coal gasification system according to claim 1, characterized in that: The reaction section (1) is a combustion chamber, the heat exchange section (2) is a waste heat boiler, and the quenching section (3) is a quenching chamber.
3. The pulverized coal gasification system according to claim 1, characterized in that: A differential pressure gauge (22) is installed at the slag opening (21) to detect the pressure difference between the upper and lower ends of the slag opening (21).
4. The pulverized coal gasification system according to claim 1, characterized in that: The slag pool pump (11) is connected to the slag water output pipe (110) and the fresh water inlet pipe (111).
5. The pulverized coal gasification system according to claim 1, characterized in that: The slag lock hopper flushing water tank (8) is provided with an inlet pipe (81) and an outlet pipe (82). A flushing water inlet pipe (83) and a flushing water return pipe (84) are provided between the slag lock hopper flushing water tank (8) and the slag lock hopper (7).
6. The pulverized coal gasification system according to claim 1, characterized in that: The lock bucket circulation pump (9) is connected to the lower part of the quench section (3) through the slag lock bucket circulation pump return water pipe (91).
7. The pulverized coal gasification system according to claim 1, characterized in that: A pulverized coal flow meter (411) is installed on the pulverized coal pipeline (41), and an oxygen flow meter (421) is installed on the oxygen pipeline (42).
8. The pulverized coal gasification system according to claim 1, characterized in that: The upper part of the reaction section (1) is equipped with pressure gauge No. 1 (101), the upper part of the heat exchange section (2) is equipped with pressure gauge No. 2 (102), the middle part of the heat exchange section (2) is equipped with thermometer (104), and the quenching section (3) is equipped with pressure gauge No. 3 (103).